What drives legislative activism by the EU Commission in some policy areas and legislative apathy in others? Which policy areas does the Commission prioritize when seeking to widen or deepen the EU policy competencies and why? In this paper, we argue that the Commission behaves strategically when deciding whether to expand the supranational authority in a policy domain. The Commission exploits the politicization dynamics and opts to broaden the Union competences over policies that are seen as salient by the population of the Union and/or widely supported by the European citizens. Yet, when faced with a substantial political discord among the member-state governments, the Commission is likely to turn to consolidating the pre-existing EU’s policy competencies rather than seek to broaden them. Unpacking these distinct rationales of responsiveness, the study sheds light onto the underlying reasons for the puzzling overall decrease of legislative activity of the Commission in the post-Lisbon period. To map the variance of the legislative activity of the Commission across policies and over time, we analyze the content of the legislative proposals submitted between 2009-2020 using cutting-edge text-analysis techniques. We rely on Eurobarometer surveys and national parliamentary debates to obtain information on the preferences of the EU public and member-states governments, respectively. Our results add to the extant literature on EU responsiveness and contribute to a better understanding of underlying determinants of divergent speed of integration across policy areas and over time.